These are the source candidate and firmware images provided on TP-Link's website for this product. Note that as of 2024-02-02, the version 1.1.2 firmware does not seem to be available on the website anymore, so we are re-posting it here.
TP-Link Deco X90 V1 1.1.2 round 6 of N
Device: Deco X90 V1
Released: Jan. 23, 2024
denver — Feb. 2, 2024, 8:03 p.m.
A firmware image is produced when following the steps, but it lacks many kernel modules found in the stock firmware image. There may be additional issues, and installation has not been tested due to the incompleteness so far.